Quarks

Quarks

1. Radioactivity

   • isotope- atom with same number of protons but different number of neutrons
   • α radiation- nucleon number decreases by 4 and atomic number by 2, also emits α particle
     • helium atom
   • β radiation- nucleon number not changed, atomic number increases by 1, β and antineutrino emitted
     • fast moving electrons
   • γ radiation- emitted by nucleus with too much energy following α or β decay
     • electromagnetic radiation

2. Hadrons

   • particles + antiparticles that interact through strong the interaction
   • baryons - 3 quarks, protons and neutrons
   • mesons- made up of quark+antiquark, pions and K mesons
   • +1 = Baryon, 0 = not a baryon and -1 = baryon antiparticle
   • 2nd generation = strange and charm
   • 3rd generation= top and bottom

3. Leptons

   • fundamental particles with no internal structure
   • electron and electron neutrino = first generation
   • muon and muon neutrino = second generation
   • tau and tau-neutrino = third generation
   • muon and tau are heavier versions of electron but have same charge

4. Fundamental forces

   • gravitational- weakest but acts over an infinite distance
   • electromagnetic- infinite range, holds atoms and molecules together
   • weak nuclear- range does not extend beyond nucleus
   • strong nuclear- strongest but has short range acts between neighbouring nucleons